Raynaud Syndrome

History

There are associated vascular and non-vascular causes for secondary Raynaud phenomenon but it is not classified under Raynaud disease. [1] [2] [3] [4] [5]

Colour change of the extremities following an exposure to a stimulus

Raynaud phenomenon or freezing finger syndrome is characterized by three phasic color change when challenged with a predisposing factor. First when the stimulus is applied, there is an immediate vasoconstriction causing the affected areas to appear blood-less or pale. The extent of vasoconstriction is easily visible separated. After that, since the blood flow is insufficient to keep the oxygenated blood running, the affected blood vessels become desaturated and the areas are cynosed, so they appear blue. Once the stimulus is withdrawn, the blood vessels dilate and the rapid blood flow established, causing the affected areas to look redder, or hyperemic. Skin color comes back to the natural color with time. The most commonly affected areas are the extremities. i.e. finger-tips, toe-tips, earlobes, lips and nipples. The symptoms are always bilateral. The color change may not be very visible in the dark skinned population. The color change is reversible and reproducible. The usual predisposing factors are cold and emotional upset. It is hypothesized that increased level of sympathetic activity is the causative factor in primary Raynaud syndrome. [6] [7] [8] [9] [10] [11] [12] [13]

Pain of the affected areas

Due to collection of noxious metabolites in the process of ischemia. [6] [14] [15]

Examination

Fact

Explanation

Normal skin color if not stimulated

The patients with Raynaud syndrome have a normal skin color unless provoked by a stimulus.

Color change if presented with a recognized stimulus.

There is a triphasic color change in the extremity when met with a recognized stimulus. i.e. cold. There is a sharp demarcation between the affected areas due to the color change. [1] [2] [3] [4] [5] [6] [7]

Wounds and gangrenes

There can be loss of tissues in the extremities due to chronic ischemia. Unlike in secondary Raynaud disease, in primary condition gangrenes and widespread tissue losses are rare. [9] [10] [11]

Probable causes for occlusive arterial disease (i.e. atherosclerosis, dyslipidemia) and other co-existent manifestations (i.e. angina pectoris) should be evaluated. Occlusive arterial disease is a life threatening condition that can lead to loss of a limb unless attended to first in emergency setting. Pain, bluish discoloration of limb extremities can be initial presentation. [6] [7] [8]

Thromboembolic diseases

These are the conditions where microemboli are shooted up in the systemic circulation and clogged in the end arteries of the extremities. They can manifest in the same way, with ischemia, discolored extremities. [9] [10] [11] [12] [13] [14] [15]

Reflex sympathetic dystrophy

A syndrome that is caused by surgical or traumatic nerve injuries and is characterized with pain, swelling, and vasomotor dysfunction of an extremity. Careful history taking and examination can exclude this differential. [16] [17] [18] [19] [20] [21] [22]

Investigations - for Diagnosis

Fact

Explanation

Cold challenge test

It is used to test the severity of Raynaud phenomenon. The test can be performed by measuring the skin blood flow of hand or foot that is cooled or the opposite limb, to test sympathetically mediated vasoconstriction. The blood flow is assessed by laser Doppler method. The cold is applied as cold water of 20'C. [1] [2] [3]

Laser Doppler monitoring

Superficial blood flow difference with cold exposure can be assessed with laser Doppler technique. It can be used in adjunct with other investigations such as cold challenge test. Serial monitoring helps in identifying the provocative stimuli. [4] [5] It is positive early in the course of the disease and Laser Doppler-recorded venoarteriolar reflex (VAR) response to hand lowering can be used to differentiate primary and secondary Raynaud phenomenon. [6] [7] [8] [9]

Management - General Measures

Fact

Explanation

Education of the patient and family

Educating the patient and the family about the nature of the condition, provocative factors, management options and prognosis of the disease is mandatory and helps with compliance and long term outcome. [1] [2] [3]

Lifestyle modifications,

Since there is not an underlying cause for primary Raynaud disease, lifestyle modification could be the only measure required for management. THe identified factors usually are cold/frozen drinks or food, cold air, cold water baths etc. Wearing protective socks or gloves when being exposed to such factors to prevent direct contact with them has also proved useful. Wearing body insulators is also recommended. Quitting smoking is also mandatory, since there has been strong evidence linked with smoking and Raynaud disease exacerbations. [4] [5] [6] [7] [8] [9] [10] The recognized drugs that are known to cause peripheral vasoconstriction should be avoided. i.e. nicotine, antihistamines [11]